Aluminum alloy



Patented June 14, 1932 oFFIcE PANY F 2% Drawing. 8

This invention relates to aluminum base alloys containing substantial amounts of silicon and is particularly directed to aluminum base alloys Containing silicon and small 3 amounts of calcium and titanium with or without nickel.

Aluminum base alloys containing silicon in amounts of about 3 to per cent have a wide variety of uses, especially in the lower 1 silicon ranges in the neighborhood of about 5 per cent, where they can be readily cast or worked in the form of sheet into various shapes by drawings, spinning, pressing, or

by other methods of mechanical deformation;

an alloy consisting basically of aluminum and silicon which will have such casting and fabricating properties that the alloy may be readily cast, drawn, spun, rolled, or otherwise -molded or formed into useful commercial shapes and which will also present a metal 0 surface capable of taking an exceptionally a high polish where such polish is desirable.

I have discovered that this object may be obtained by adding small quantities of titanium and calcium to aluminum. base alloys containing silicon, and I-have also discovered that a still further improvement may be effected by adding to the alloy thus compounded a relatively small percentage of nickel. While any amount of titanium higher than about 0.01 per cent is capable, is combination with the other elements of the alloy, of producing thedesired improvement, practical difiiculties in casting and forming the alloy demand that the titanium be present 'inamounts not over about 0.5 per cent, and, in the preferred alloys of the composition made in accordance with my invention, the titanium content should not exceed more than about 0.3 per cent. In order to obtain the desired results, the calcium AMEBIGA, O15 PITTSBURGH, PENNSYLVANIA, A CORPQRATION OF PENN- ALUHINUM ALLOY I a lication filed March a0, 1931. Serial No. 526,567.

need be present only in small amounts and an addition of calcium in amounts of about 0.01 to 0.1 per cent to an alloy containing aluminum, silicon, and titanium will be sufficient toproduce an alloy of the above-mentioned characteristics.

. While the aluminum base alloys containing silicon-and the small amounts of calcium and titanium above mentioned produce an alloy of good casting properties and capable of taking an exceptionally fine polish the appearance of the polished surface of the alloy is improved to some extent if there is also present in the alloy from about 0.1 to 1 per cent of nickel, and, in many cases, the addition of the nickel is to be preferred when an exceptionally high polish of pleasing appearance is desired to be obtained on the surface of the alloy.

The method by which my novel alloys containing aluminum and silicon and also calcium and titanium with or without nickel are compounded appears to have no bearing upon the ultimate efli'ect produced, and, so long as the proper percentages of each constituent are present in the final alloy, an alloy of the properties above described may be obtained by any of the well known metallurgical methods of compounding alloys. however, to produce the alloys by dissolving silicon in molten aluminum and adding. to the molten aluminum-silicon alloy the calcium, titanium, and nickel in the form of intermediate hardeners or alloys in which aluminum is the other component. After the alloy has been compounded and the articles "therefrom produced by casting, working or other manner of fabrication, they may be polished by any of the known polishing or bulling processes and it will be found that a much higher and more pleasing surface polish can be obtained than when aluminumsilicon alloys not containing the titanium and calcium are polished. My novel alloys may be readily worked and cast.

The term aluminum base alloy as used herein and in the appended claims refers to alloys containing more than about 50 per cent of aluminum.

I prefer,

I claim:

1. An aluminum base alloy containing from about 3 to 15 per cent of silicon, from about 0.01 to 0.1 percent of calcium, and

from 0.01 to 0.3 per cent of titanium.

2. An aluminum base alloy containing from about 3 to 15 per cent of silicon, from about 0.01 to 0.1 per cent of calcium, from about 0.01 to 0.3 per cent of titanium, and

10 from about 0.1 to about 1 per cent of nickel.

3. An aluminum base alloy containing from about 3 to about 15 per cent of silicon, from 0.01 to 0.5 per cent of titanium, and from 0.01 to 0.1 per cent of calcium.

15 4. An aluminum base alloy containing from about 3 to about 15 per cent of silicon, from about 0.1 to about 1.0 per cent of nickel, from 0.01 to 0.5 per cent of titanium, ami from 0.01 to 0.1 percent of calcium.

EARL McKINLEY GINGERIGH. 

